Pitch-propelled vehicle

ABSTRACT

A method, system and apparatus for carrying a user including a board for supporting the user, a ground-contacting member coupled with the board, a motorized drive assembly coupled with the ground-contacting member and one or more sensors coupled with the drive assembly. In operation, the drive assembly adjusts the velocity of the ground-contacting member based on one or more distances of the board from a surface below the board as detected by the sensors. As a result, the system is able to maintain a desired velocity when ascending, descending or traversing uneven ground without the need for excessive and sometimes impossible tilting of the board.

RELATED APPLICATION(S)

This Patent Application is a continuation-in-part of co-pending U.S.patent application Ser. No. 14/936,572, filed Nov. 9, 2015, and titled“PITCH-PROPELLED VEHICLE”, which is a continuation of U.S. patentapplication Ser. No. 14/058,937, filed Oct. 21, 2013, and titled“PITCH-PROPELLED VEHICLE”, all of which are hereby incorporated byreference in their entirety.

FIELD OF THE INVENTION

The present invention relates to the field of vehicles. Morespecifically, the present invention relates to the field of vehicleshaving pitch-sense based motion.

BACKGROUND OF THE INVENTION

There are many known types of commercial and recreational vehicles fortransporting people. Most of these vehicles are designed to be stablewith respect to tipping by incorporating three or four wheels thatbalance and support the user and the remainder of the vehicle. Forexample, a skateboard is a well known vehicle that uses four wheels thatare positioned to create a stable platform for the board and the user inall directions. However, many users enjoy the challenge of riding atleast partially unstable vehicles. A scooter is an example of such apartially unstable vehicle because it is stable in the direction of thealignment of the wheels, but can tip side to side perpendicular to thealignment. Similarly, a unicycle, which uses a single wheel, is unstablewith respect to tipping in all directions.

Recently, vehicles, such as a segway, have been created that utilizebalance assisting systems to not only help stabilize an otherwiseunstable vehicle, but also utilize the tipping of the vehicle to controlits movement. Although this stabilization and movement control workswell on even surfaces, it is unable to adequately operate on or adjustto uneven surfaces which are often encountered when riding such avehicle. Further, they are able to be both complicated and expensive indesign, which increases the likelihood of breaking down, the cost ofrepairs and the overall cost of manufacture.

SUMMARY OF THE INVENTION

A vehicle for carrying a user including a board for supporting the user,a ground-contacting member coupled with the board, a motorized driveassembly coupled with the ground-contacting member and one or moresensors coupled with the drive assembly. In operation, the driveassembly adjusts the velocity of the ground-contacting member based onone or more distances of the board from a surface below the board asdetected by the sensors. As a result, the system is able to maintain adesired velocity when ascending, descending or traversing uneven groundwithout the need for excessive and sometimes impossible tilting of theboard.

In one aspect the present application relates to a vehicle for carryinga user. The vehicle comprises a board having a plurality of detachedsections coupled together by one or more hinges such that the sectionsare able to pivot about the hinges, a single ground-contacting membercoupled with the board and a motorized drive assembly coupled with theground-contacting member, wherein the drive assembly adjusts thevelocity of the ground-contacting member. In some embodiments, theground-contacting member rotates about a hollow axle having an exposedchannel that extends though the hollow axle. In some embodiments, theground-contacting member rotates about an axle and axle acts as a pin ofthe hinges such that the sections pivot about the axle. In someembodiments, the board has one or more additional hinges that with theone or more hinges rotatably couple together three of the sections ofthe board. In some embodiments, the board comprises one or more handlesthat are each defined by one of the group consisting of a hole thatextends through the board or a channel that extends only partially intothe bottom of the board. In some embodiments, two or more of thesections of the board house at least one electronic component of thedrive assembly and the board further comprises one or more interfacesthat electrically couple together two or more of the electroniccomponents from different ones of the two or more of the sections whenthe board is in an unfolded position. In some embodiments, the vehiclefurther comprises one or more sensors coupled with the drive assembly,wherein the drive assembly adjusts the velocity of the ground-contactingmember based on one or more distances of the board from a surface belowthe board as detected by the sensors. In some embodiments, the board iselongated along a dimension in a fore-aft plane that aligns with theforward and reverse directions of travel of the vehicle. In someembodiments, one or more fore sensors of the sensors are positioned atthe fore end of the elongated dimension of the board and one or more aftsensors of the sensors are positioned at the aft end of the elongateddimension of the board. In some embodiments, the drive assembly adjuststhe velocity of the ground-contacting member based on the one or moredistances by using the distances to calculate a pitch of the board withrespect to the surface and applying a force to the ground-contactingmember in order to achieve a predefined velocity of theground-contacting member that corresponds to the pitch. In someembodiments, the pitch is calculated by determining a difference betweenthe one or more distances and an average of two or more of the distancessuch that the drive assembly adjusts for unevenness in the surface. Insome embodiments, the board as balanced by the ground-contacting memberis unstable with respect to tipping along the fore-aft plane when themotorized drive assembly is not in operation, and the motorized driveassembly is configured to automatically balance the board with respectto tipping along the fore-aft plane when the motorized drive assembly isin operation.

Another aspect is directed to a method of operating a vehicle having anelongated board. The method comprises providing a vehicle comprising aboard having a plurality of detached sections coupled together by one ormore hinges such that the sections are able to pivot about the hinges, asingle ground-contacting member coupled with the board and a motorizeddrive assembly coupled with the ground-contacting member, wherein thedrive assembly adjusts the velocity of the ground-contacting member,moving the board between an unfolded position into a folded position bypivoting the sections about the hinges, wherein ends of two of thesections that are on opposite sides of the board in the unfoldedposition are closer together in the folded position. In someembodiments, the ground-contacting member rotates about a hollow axlehaving an exposed channel that extends though the hollow axle. In someembodiments, the ground-contacting member rotates about an axle and axleacts as a pin of the hinges such that the sections pivot about the axle.In some embodiments, the board has one or more additional hinges thatwith the one or more hinges rotatably couple together three of thesections of the board. In some embodiments, the board comprises one ormore handles that are each defined by one of the group consisting of ahole that extends through the board or a channel that extends onlypartially into the bottom of the board. In some embodiments, two or moreof the sections of the board house at least one electronic component ofthe drive assembly and the board further comprises one or moreinterfaces that electrically couple together two or more of theelectronic components from different ones of the two or more of thesections when the board is in an unfolded position. In some embodiments,the vehicle further comprises one or more sensors coupled with the driveassembly, wherein the drive assembly adjusts the velocity of theground-contacting member based on one or more distances of the boardfrom a surface below the board as detected by the sensors. In someembodiments, the board is elongated along a dimension in a fore-aftplane that aligns with the forward and reverse directions of travel ofthe vehicle. In some embodiments, one or more fore sensors of thesensors are positioned at the fore end of the elongated dimension of theboard and one or more aft sensors of the sensors are positioned at theaft end of the elongated dimension of the board. In some embodiments,the drive assembly adjusts the velocity of the ground-contacting memberbased on the one or more distances by using the distances to calculate apitch of the board with respect to the surface and applying a force tothe ground-contacting member in order to achieve a predefined velocityof the ground-contacting member that corresponds to the pitch. In someembodiments, the pitch is calculated by determining a difference betweenthe one or more distances and an average of two or more of the distancessuch that the drive assembly adjusts for unevenness in the surface. Insome embodiments, the board as balanced by the ground-contacting memberis unstable with respect to tipping along the fore-aft plane when themotorized drive assembly is not in operation, and the motorized driveassembly is configured to automatically balance the board with respectto tipping along the fore-aft plane when the motorized drive assembly isin operation.

Yet another aspect is directed to a motorized skateboard-like vehiclefor carrying a user. The vehicle comprises a board having a plurality ofdetached sections coupled together by one or more hinges such that thesections are able to pivot about the hinges, wherein the board comprisesone or more handles that are each defined by one of the group consistingof a hole that extends through the board and further wherein two or moreof the sections of the board house at least one electronic component ofthe drive assembly and the board further comprises one or moreinterfaces that electrically couple together two or more of theelectronic components from different ones of the two or more of thesections when the board is in an unfolded position, a singleground-contacting member coupled with the board and a motorized driveassembly coupled with the ground-contacting member, wherein the driveassembly adjusts the velocity of the ground-contacting member, whereinthe ground-contacting member rotates about a hollow axle having anexposed channel that extends though the hollow axle.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1A illustrates a side view of a pitch propelled vehicle accordingto some embodiments.

FIG. 1B illustrates a top perspective view of a pitch propelled vehicleaccording to some embodiments.

FIG. 1C illustrates a bottom perspective view of a pitch propelledvehicle according to some embodiments.

FIG. 1D illustrates a top view of a pitch propelled vehicle according tosome embodiments.

FIG. 1E illustrates a bottom view of a pitch propelled vehicle accordingto some embodiments.

FIG. 2 illustrates a block diagram of an exemplary controller accordingto some embodiments.

FIG. 3 illustrates a flow chart of a method of carrying a user accordingto some embodiments.

FIG. 4A illustrates an unfolded side view of a pitch propelled vehiclewith a folding feature according to some embodiments.

FIG. 4B illustrates a folded side view of a pitch propelled vehicle witha folding feature according to some embodiments.

FIG. 4C illustrates an unfolded isometric view of a pitch propelledvehicle with a folding feature according to some embodiments.

FIG. 4D illustrates a folded isometric view of a pitch propelled vehiclewith a folding feature according to some embodiments.

FIG. 4E illustrates an unfolded side view of a pitch propelled vehiclewith a folding feature according to some embodiments.

FIG. 4F illustrates a folded side view of a pitch propelled vehicle witha folding feature according to some embodiments.

FIG. 5 illustrates a flow chart of a method of using a pitch propelledvehicle with a folding feature according to some embodiments.

DETAILED DESCRIPTION

Embodiments of a system, device and method of a pitch-propelled vehicleincluding a board for supporting the user, a ground-contacting membercoupled with the board, a motorized drive assembly coupled with theground-contacting member and one or more sensors coupled with the driveassembly. In operation, the drive assembly adjusts the velocity of theground-contacting member based on one or more distances of the boardfrom a surface below the board as detected by the sensors. As a result,the vehicle provides the advantage of altering the pitch/velocityrelationship when traveling uphill, downhill or on uneven surfaces thatmake a pitch/velocity relationship with respect to gravity untenable. Asused herein the term “ground” is able to be the earth, the floor or anyother surface over which the vehicle 100 is able to travel.

FIGS. 1A-1E illustrate a pitch-propelled vehicle 100 according to someembodiments. As shown in FIGS. 1A-1E, the vehicle 100 comprises aplatform or board 102, a guard 103, a ground-contacting member 104, adrive assembly 106(a-g), one or more grips 108 and one or more scrapers109 all operatively coupled together. Alternatively, one or more of theabove components are able to be omitted. The board 102 is able to berigid and detachably coupled to the ground-contacting member 104 suchthat when balanced the ground-contacting member 104 is able tohold/support the board 102 and the board 102 is able to support therider(s) above the ground. In some embodiments, the board 102 comprisesa member fastener assembly 105 that detachably couples theground-contacting member 104 and/or some or all of the drive assembly106(a-g) to the board 102. As a result, the ground-contacting member 104is able to be selectively separated from or coupled to the board 102 byunlocking or locking the member fastener 105. This locking/unlockingmechanism of the member fastener 105 is able to be a key lock, asnap-fit connection, screw on/off or other types of fasteners that areable to hold the ground-contacting member 104 and/or some or all of thedrive assembly 106(a-g) in a locked position with respect to the board102. Thus, the vehicle 100 provides the advantage of easily replacing orrepairing the board 102 and/or the ground-contacting member 104 usingthe member fastener 105.

As shown in FIG. 1A, the guard 103 shields a rider from the top of theground-contacting member 104 as it protrudes through the board 102. Thisprovides the advantage of preventing a rider from being injured bystepping on or otherwise contacting the ground-contacting member 104.Although as shown, the guard 103 covers a portion of the sides of theground-contacting member 104 as it protrudes through the top of theboard 102, it is understood that more or less (e.g. all) of theground-contacting member 104 is able to be shielded by the guard 103. Asshown in FIG. 1A, two scrapers 109 are positioned on either side of theground-contacting member 104 such that the scrapers 109 are adjacent toand/or surround lower ends of the member 104. As a result, the scrapers109 are able to protect the vehicle 100 from debris such as rocks fromentering the vehicle 100 between the ground-contacting member 104 andthe board 102. In particular, the scrapers 109 are able to be sized tofill any gap between the ground-contacting member 104 and the undersideof the board 102 and/or be positioned as close as possible to theground-contacting member 104 to block debris from entering the vehicle100 through such a gap. Further, it is contemplated that the guard 103and/or grips 108 are able to be similarly positioned on the top of theboard 102 to block debris from entering the vehicle 100 through a gapbetween the board 102 and the ground-contacting member 104 on the topside of the board 102. Additionally, it is contemplated that more orless than two scrapers 109 are able to be used.

The board 102 is able to have a thickness and broad and/or substantiallyflat top/bottom surface for receiving/supporting the feet of a rider. Insome embodiments, the board 102 is able to have an oblong top surfacewith an elongated dimension in a fore/aft direction similar to the boardof a skateboard. In particular, this elongated dimension is able tosubstantially align with the orientation of the ground-contacting member104 such that a rider is able to ride the board 102 sideways to thedirection of travel like one would ride a skateboard. Alternatively, thetop surface of the board 102 is able to be substantially circular,ovular, rectangular, square or otherwise shaped. As shown in FIGS.1A-1E, the board 102 is able to angle upwards at the fore and aft endsin order to provide better control to a rider and to prevent the feet ofthe rider from sliding off the board 102. Alternatively, the board 102is able to be flat or bend downwards or upwards at one or both of theends at the same or different angles. In some embodiments, the board 102is at least partially hollow such that the board 102 is able to houseand protect some or all of the drive assembly 106, the grips 108 and/orthe ground-contacting member 104. Alternatively, the board 102 is ableto be solid. As shown in FIGS. 1B and 1D, the board 102 is able to havea textured surface 112 and/or include textured pads 112 coupled to thetop surface of the board 102 in order to improve traction between thefeet of the rider and the surface of the board 102.

As shown in FIGS. 1A-1E, the vehicle 100 comprises two grips 108positioned adjacent to the member fastener 105 on the fore and aft endsof the board 102. Alternatively, any number of grips 108 are able to beused and positioned on any portion of the board 102. For example, theboard 102 is able to have multiple coupling locations configured toreleasably couple to one or more grips 108 such that a user is able toselect an ideal location and number of grips to releasably attach to theboard 102. Alternatively or in addition, the coupling locations are ableto be adjustable such that for each coupling location (and/or grip 108)a user is able to adjust the position of the grip from a range ofpositions enabled by the coupling location. Thus, the board 102 andgrips 108 provide the advantage of enabling a user to adjust the width,orientation, number and/or other characteristics of the grips 108 inorder to best grip the vehicle 100 with their feet. In the same manner,one or more of the grips 108 are able to be replaced on the board 102with grips 108 of different sizes, colors, shapes and othercharacteristics as desired. In some embodiments, as shown in FIGS.1A-1E, one or more of the grips 108 are able to be wholly or partiallytextured in order to increase the ability of a user to hold onto thegrips 108 with their feet. Alternatively, the grips 108 are able to beomitted.

As shown in FIGS. 1A-1E, the ground-contacting member 104 is able tocomprise a single wheel. In some embodiments, the ground-contactingmember is able to be a wheel or wheels that have a small width such as1.5 inches or less, or ⅕th the width of the board 102 or less, whichenables the vehicle 100 to more easily be turned by tilting the board102 and the wheel 104 to the left or the right side. Additionally,because the member 104 is detachably coupled to the board 102 asdescribed above, members 104 having different widths and/or otherdimensions are able to be interchanged as desired to adjust thecharacteristics of the balance and turning of the ground-contactingmember 104 and thereby the vehicle 100. Alternatively, theground-contacting member 104 is able to comprise, individually or incombination, wheels, balls, arcuate sections of a wheel or ball,clusters of wheels, tracks, treads or other types of ground-contactingmembers well known in the art. Further, although only a singleground-contacting member 104 is shown, a plurality of ground-contactingmembers 104 are contemplated. In some embodiments, the ground-contactingmember 104 is able to comprise a plurality of grooves for operablecoupling to the drive assembly 106 in order to be rotated and/orotherwise driven by the drive assembly 106. In such embodiments, themember 104 is able to be off-center with respect to the board 102, whichenables the board 102 to be closer to the ground when supported abovethe ground by the member 104. Alternatively or in addition, other powertransfer mechanisms are able to be used such as an axle wherein theboard 102 is centered about the axle and/or other mechanisms well knownin the art.

As shown in FIGS. 1A-1E, the drive assembly 106 comprises one or moremotors 106 a, batteries 106 b, controllers 106 c, rider sensors 106 d,ground sensors 106 e and/or user displays 106 f, safety elements 106 gall operably coupled together in order to operate the vehicle 100.Alternatively, the drive assembly 106 is able to comprise more or lesscomponents and/or more or less quantities of each component. Althoughshown in particular positions within FIGS. 1A-1E, it is understood thatone or more of the components of the drive assembly 106 are able to bepositioned anywhere on or within the board 102. For example, in someembodiments only a single user display 106 f is able to be used or theuser displays 106 f are able to be omitted. The drive assembly 106 ishoused by the board 102. As a result, the board 102 is able to protectthe drive assembly 106 from damage. Alternatively, one or morecomponents of the drive assembly 106 are able to be fully or partiallyexposed. Although as shown in FIGS. 1C and 1E the vehicle 100 comprisesa finite number of motors 106 a, batteries 106 b, controllers 106 c,rider sensors 106 d, ground sensors 106 e, user displays 106 f and/orsafety elements 106 g, it is understood that more or less of each arecontemplated including the omission of one or more of the components.

The one or more motors 106 a are operably and/or mechanically coupled tothe ground-contacting member 104 in order to cause the ground-contactingmember 104 to rotate and thereby stabilize and move the vehicle 100. Insome embodiments, the motors 106 a are able to engage or couple with theplurality of grooves within the ground-contacting member 104 in order totranslate motion/power of the motors 106 a to the ground-contactingmember 104. For example, one or more of the motors 106 a are able to beelectric and/or direct drive motors (e.g. motors with a direct drivemechanism that couples to the member without any reductions such as agearbox) that directly mechanically couple with the grooves of themember 104 in order to cause the member 104 to rotate/actuate ascontrolled by the controllers 106 c. As a result, in such embodimentsthe vehicle 100 is able to provide the advantages of increasedefficiency due to no intermediary power loss, reduced noise and longerlifetime due to less/simpler parts, high torque at lower revolutions perminute and faster/precise positioning by eliminating mechanicalbacklash, hysteresis and elasticity. Alternatively, one or more of themotors 106 a are able to be non-direct drive and/or electric motors suchas combustion, hydraulic or other types of direct or indirect drivemotors.

The one or more batteries 106 b are able to be coupled with and providepower to the motors 106 a, controllers 106 c, rider sensors 106 d,ground sensors 106 e, user displays 106 f and/or safety elements 106 g.In some embodiments, the batteries 106 b are able to be rechargeablebatteries that provide electrical power to the vehicle 100. In suchembodiments, the vehicle 100 is able to comprise a port or plug fromreceiving electrical power from an outside source such as a poweroutlet. Alternatively in such embodiments, the vehicle 100 is able tocomprise one or more solar arrays that are able to recharge the one ormore batteries 106 a. Alternatively, the batteries are able to benon-rechargeable such that they must be replaced periodically. In someembodiments, the batteries 106 b are able to be positioned across fromthe motors 106 a within the board 102 such that they balance the weightof the motors 106 a within the board 102 about the ground-contactingelement 104. Alternatively, the batteries 106 b are able to bepositioned anywhere on or within the board 102.

The rider sensors 106 d are able to be coupled to the ground-contactingmember 104 and/or the board 102 such that the sensors 106 d are able tosense when a user (or payload) is on the board 102. For example, one ormore of the rider sensors 106 d are able to be positioned on the topsurface of the board 102 in order to sense when the feet of a rider orother payload is on the surface of the board 102. Alternatively, therider sensors 106 d are able to be positioned at other points on thevehicle 100. For example, one or more of the rider sensors 106 d areable to be positioned at the coupling point (e.g. the member fastener105) between the board 102 and the ground-contacting member 104 in orderto measure the force applied to ground-contacting member 104 via theboard 102 due to the weight of a user on the board 102. In someembodiments, the rider sensors 106 d are able to comprise resistancesensors, force sensors, acoustic sensors, visual sensors, capacitivesensors or other types of sensors as are well known in the art. Theforce sensors are able to measure weight or the force at a point on theboard 102 and/or the ground-contacting member 104, wherein a user orpayload is determined to be present when the force measures exceeds apredefined threshold. The acoustic sensors (e.g. sonar) are able tooutput an acoustic signal and based on any echo of the signal input bythe sensors determine whether a user or payload is on the board 102.Similarly, the visual sensors (e.g. infrared) are able to output avisual signal (or simply utilize external visual signals) and determineif a user or payload is on the board 102 based on measured input lightsignals. Also, the capacitive sensors are able to detect a change incapacitance between the elements coupled to the board 102, wherein auser or payload is determined to be present when the capacitance betweenthe elements is increased above a predefined threshold.

The ground sensors 106 e are operatively (e.g. electrically) coupledwith the controllers 106 c in order to transmit signals to thecontrollers 106 c based on their input. As shown in FIGS. 1C and 1E, theground sensors 106 are able to be partially housed within and positionedon the bottom of the board 102 on either end (fore and aft) of theground-contacting member 104. As a result, the ground sensors 106 e areable to measure the distance between the board 102 and the ground onboth ends of the board 102. Therefore, as described below with referenceto the controllers 106 c, based on these measured distances (and thepreset distances of the sensors 106 e from the ground-contacting member104) the controllers 106 c are able to determine the pitch of the board102 relative to the ground. Alternatively, ground sensors 106 e are ableto be positioned on other portions of the board 102. In someembodiments, the ground sensors 106 e are only positioned on a singleend (fore or aft) of the board 102.

The ground sensors 106 e are able to be acoustic sensor (e.g. sonarbased sensors) that output an acoustic signal and then determine adistance between the sensor and the ground or another object based onthe echo or reflection of the acoustic signal as received by the sensor106 e. Alternatively, the ground sensors 106 e are able to be lightsensors that, for example, output a light signal (e.g. infrared) andthen determine a distance between the sensor and the ground or anotherobject based on the reflection of the light signal as received by thesensor 106 e. Alternatively, the ground sensors 106 e are able tocomprise acoustic sensors, light sensors, radio frequency sensors, forcesensors, pressure sensors or a combination thereof.

The user displays 106 f are operatively (e.g. electrically) coupled withthe controllers 106 c in order to receive display commands from thecontrollers 106 f. As a result, the user displays 106 f are able todisplay information to the user about the vehicle 100 based on datareceived from the controllers 106 c. For example, the displays 106 f areable to display a charge level of the batteries 106 b, a current speedof the vehicle 100, revolutions per minute of the ground-contactingmember 104, a pitch level and direction of the board 102, a warning orrepair message if the vehicle is in an unsafe or damaged condition, acurrent time and/or other types of information as are well known in theart. As shown in FIGS. 1B and 1D, the displays 106 f are positioned atthe fore and aft ends of the board 102. Alternatively, the displays 106f are able to be positioned on other portions of the board 102.

The safety elements 106 g are able to comprise lights and/or speakersthat output light and/or sound from the vehicle 100. For example, thesafety elements 106 g are able to comprise lights that light an areaaround the vehicle 100 such as the front path of the vehicle 100 likeheadlights on a car and/or the back of the vehicle 100 like tail lightson a car. In some embodiments, the safety element 106 g closest to thedirection of travel displays a white light to illuminate the upcomingroad/surface. In some embodiments, the safety element 106 g closest tothe rear of the direction of travel displays a red light to indicate theback of the vehicle 100 and/or is able to be controlled by thecontroller 106 c to light up when the vehicle 100 isdecelerating/braking like car tail lights. In some embodiments, thecolor and/or operation of the safety elements 106 g are able to switchbased on the direction of travel of the vehicle 100. For example, asafety element 106 g acting as a tail light is able to switch operationto act as a head light and vice versa when direction of the vehicle 100is reversed. In some embodiments, the safety elements 106 g areconfigured to sense ambient light and only activate when ambient lightdetected is less than a threshold level. Alternatively or in addition,the safety elements 106 g are able to be activated or de-activatedmanually.

In some embodiments, the safety elements 106 g are able to output awarning noise that warns people that the vehicle 100 is near. In someembodiments, the noise is able to change in tune, frequency or otherwisebased on the acceleration, deceleration or other operations of thevehicle 100. In some embodiments, the safety elements 106 g are able tocouple with an audio source via the controller or separately such thatthey are able to produce audio based on the signal received from theaudio source. For example, the safety elements 106 g are able to playmusic from a radio or antenna and/or from another audio source device(e.g. telephone, ipod). The safety elements 106 g are operatively (e.g.electrically) coupled with the controllers 106 c in order to receivecommands from the controllers 106 f. As a result, the user displays 106f are able to operate based on data received from the controllers 106 c.As shown in FIGS. 1B and 1D, the safety elements 106 g are positioned atthe fore and aft ends of the board 102. Alternatively, the safetyelements 106 g are able to be positioned on other portions of the board102.

The controllers 106 c are operably coupled to the motors 106 a, therider sensors 106 d, the ground sensors 106 e, the user displays 106 fand/or safety elements 106 g in order to control their operationaccording to a predefined operation protocol module as described below.In some embodiments, the controllers 106 c and one or more othercomponents of the vehicle 100 are able to be coupled together by acontroller area network (CAN) bus. Alternatively, other networks areable to be used. FIG. 2 illustrates a block diagram of an exemplarycontroller 106 c according to some embodiments. As shown in FIG. 2, thecontroller 106 c comprises a network interface 202, a memory 204, aprocessor 206, I/O device(s) 208, a bus 210 and a storage device 212.Alternatively, one or more of the illustrated components are able to beremoved or substituted for other components well known in the art. Thechoice of processor is not critical as long as a suitable processor withsufficient speed is chosen. The memory 204 is able to be anyconventional computer memory known in the art. The storage device 212 isable to include a hard drive, CDROM, CDRW, DVD, DVDRW, flash memory cardor any other storage device. The controller 106 c is able to include oneor more network interfaces 202. An example of a network interfaceincludes a network card connected to an Ethernet or other type of LAN.The I/O device(s) 208 are able to include one or more of the following:keyboard, mouse, monitor, display, printer, modem, touchscreen, buttoninterface and other devices. The operation protocol 230 used to operatethe vehicle 100 is able to be stored in the storage device 212 andmemory 204 and processed as programs are typically processed. More orless components shown in FIG. 2 are able to be included in thecontroller 106 c. In some embodiments, operation protocol hardware 220is included, wherein the hardware implements a portion or all of theoperation protocol. Although as shown in FIG. 2, the controller 106 cincludes software 230 and hardware 220 for implementing the operationalprotocol, the operation protocol is able to be implemented in hardware,firmware, software or any combination thereof. Additionally, thecontroller 106 c is able to comprise one or more components not shown inFIG. 2 that enable the controller 106 c to perform commutation and othercalculations. For example, the controller 106 c is able to comprise anencoder for encoding the position of the ground-contacting member 104relative to the board 102 or another static marker. These components arewell known in the art and not described herein for the sake of brevity.

In operation, when implementing the operation protocol, the controller106 c determines the distance between one or both the fore and aft endsof the board 102 and the ground (or surface below the board 102) basedon the input from one or more of the ground sensors 106 e. Subsequently,based on the determined distance(s), the controller 106 c calculates apitch of the board 102 relative the ground and causes the motors 106 ato apply a force to the ground-contacting member 104 based on thedetermined board pitch. For example, if the controller 106 c determinesthat the board 102 is pitched at a first level, the controller 106 ccauses the ground-contacting member 104 (via the motors 106 a) to slowdown, speed up and/or reverse direction in order to approach andeventually match a desired velocity, acceleration and/or torqueassociated with the pitch of the first level. As a result, in general,when a user leans to pitch the board 102 in the aft or fore directionsrelative to the ground, the controller 106 c will cause theground-contacting member 104 and thus the vehicle 100 to move (orreverse direction and then move) in the aft or fore directions,respectively. As a result, the vehicle 100 provides the advantage ofcompensating for changes in ground level when determining the pitch ofthe board because the board pitch is determined relative to the ground.This is important when the vehicle 100 is traversing uneven surfaces asthey can limit the ability of the board to pitch. For example, insystems where pitch is based on a deviation of the board angle withrespect to gravity, when going up hill it can become difficult orimpossible to keep the board pitched forward because the hill/groundblocks further pitching. In contrast, the pitch-propelled vehicle 100described herein is able to determine the pitch relative to thehill/ground such that less forward pitch is still able to cause thevehicle 100 to move forward at the desired rate.

In some embodiments, the board pitch is dynamically determined based onan average of the current distance detected between the fore end of theboard 102 and the surface and the current distance detected between theaft end of the board 102 and the surface as detected by one or more ofthe ground sensors 106 e. Alternatively, the board pitch is able to bedynamically determined by the distance detected between only one end ofthe board 102 and the surface. Alternatively, the board pitch is able tobe dynamically determined based on the difference between the currentdistance detected between the fore end of the board 102 and the surfaceand the current distance detected between the aft end of the board 102and the surface.

In some embodiments, the controller 106 c takes into considerationdetected changes the in surface that are about to be traversed by theground-contacting member 104 when adjusting the force applied to theground-contacting member 104 in order to achieve the desired velocity,acceleration and/or torque. In particular, because the sensors 106 e area distance in front (and behind) the ground-contacting member 104, theyare able to detect (or map) characteristics of and changes in theground/surface before the ground-contacting member 104 reaches thechanges. As a result, the controller 106 c is able to adjust the commandsignals sent to the ground-contacting member 104 based on thecharacteristics/changes in the ground before the ground-contactingmember 104 has encountered the characteristics/changes. In suchembodiments, the controller 106 c is able to determine a time in thefuture when the ground-contacting member 104 is expected to reach thecharacteristics/changes and adjust the timing of the control signalsassociated with the characteristics/changes to correspond to thedetermined time. The time is able to be determined based on the currentposition of the ground-contacting member 104 relative to thecharacteristics/changes and the velocity, acceleration and/or torque ofthe ground-contacting member 104.

For example, if the controller 106 c detects an upcoming inclination ofthe surface (based on the current direction of travel, a previouslydetermined distance and the currently determined distance between thesurface and one or more of the ground sensors 106 e on leading side ofthe direction of travel), the controller 106 c is able to increase theamount of force applied to the ground-contacting member 104 tocompensate for the anticipated upcoming inclination. Similarly, theforce is able to be decreased to compensate for anticipated upcomingdeclination. In other words, even if the current detected pitchcorresponds to a first force level, a higher or lower force level isable to be applied in anticipation of the detected or mappedcharacteristics/changes. As a result, the vehicle 100 provides theadvantage of providing predictive control of the ground-contactingmember 104 to compensate for incoming obstacles and terrain.

In order to adjust the actuation of the motors 106 a (and therefore theground-contacting member 104), the controller 106 c finely encodes (e.g.greater than 1,000 counts per revolution granularity) and monitors theposition of the ground-contacting member 104 relative to the board 102.Using this detected current position as feedback, the controller 106 cis able to utilize sinusoidal commutation to control the actuation ofthe motors 106 a and thus the force applied to the ground-contactingmember 104. This provides the advantage of creating smoother ridingexperience by eliminating the cogging produced by other commutationmethod especially at lower speeds. Alternatively, other types ofcommutation, such as trapezoidal (or “six-step”) commutation, are ableto be used. In some embodiments, the controller 106 c is able toincorporate a control loop feedback mechanism in order to analyze andadjust/compensate the control of the motors 106 a based on the feedback(i.e. the detected current position of the ground-contacting member104). For example, the controller 106 c is able to incorporate a closedloop proportional-integral-derivative (PID) control feedback loop thatreceives the feedback, and based on the feedback transmits one or moreerror corrections signals that the controller 106 c uses to adjust thecommutation and/or control of the motors 106 a. Alternatively, the PIDcontroller is able to be open loop and/or other types of control loopfeedback mechanisms are able to be used as are well known in the art.Alternatively, the controller 106 c is able to control operation of thevehicle 100 without feedback.

Further, instead of equating pitch (relative to ground) to a desiredtorque, the controller 106 c is able to be configured to equate pitch(relative to ground) to a desired acceleration. For example, the PIDcontrol feedback loop is able to be configured to determine accelerationerror compensation instead of torque error compensation. As a result,the PID control feedback loop and the controller 106 c provides theadvantage of being able to devote greater bandwidth to adjusting forincoming surface changes such as bumps, holes or otherinclines/declines. Alternatively, the PID control feedback loop is ableto be otherwise configured as desired in order to fine tune thecompensation of the control signal as desired. Additionally, in someembodiments, the vehicle 100 is able to comprise one or more gyroscopicand/or acceleration sensors that transmit signals to the controllers 106c such that the controllers 106 c are able to smooth or otherwisefurther process information received from the ground sensors 106 e.

FIG. 3 illustrates a flow chart of a method of carrying a user accordingto some embodiments. As shown in FIG. 3, a user/rider assumes a positionon the board 102 of the vehicle 100 at the step 302. The user/rideroperates the vehicle 100 by causing the board 102 to tilt or pitch withrespect to the surface such that the motors 106 a cause theground-contacting member 104 to propel the vehicle in the direction ofthe tilt/pitch at the step 304. In some embodiments, the userselectively couples or decouples the ground-contacting member 104 fromthe board 102 via one or more member fasteners 105 coupled to the board102 by locking or unlocking the fasteners 105. In some embodiments, theuser selectively couples or decouples the grips 108 from the board 102via one or more fasteners coupled to the board 102 by locking orunlocking the fasteners. As a result, the method provides the advantageof compensating the board pitch determination to account for changes inthe level of the ground or surface below the board 102.

The pitch propelled vehicle system, device and method described hereinhas numerous advantages. Specifically, as described above the vehicleprovides the advantage of altering the pitch/velocity relationship tocorrespond to the surface below the board (as detected by e.g. acousticsensors) when traveling uphill, downhill or on uneven surfaces that makea pitch/velocity relationship with respect to gravity untenable.Further, it provides the advantage of including foot grips that enable auser to jump or lift the board with their feet when approaching a curbor other obstacle. Moreover, it provides the advantage of enabling theground-contacting member to be selectively released/decoupled from theboard/drive assembly and selectively re-coupled or replaced with adifferent ground-contacting member. Additionally, the vehicle providesthe advantage of utilizing a direct drive motor/mechanism that moreefficiently transfers power to the ground-contacting member, providesbetter torque at lower speeds, and conserves battery life. Also, thevehicle provides the advantage of using a thin wheel or other type ofground-contacting member, which enables the vehicle to be more easilyturned via tilting the board sideways to the direction of travel.

FIGS. 4A, 4B, 4C and 4D illustrate an unfolded side view, a folded sideview, an unfolded isometric view and a folded isometric view,respectively, of a pitch propelled vehicle 400 with a folding featureaccording to some embodiments. The pitch propelled vehicle 400 shown inFIGS. 4A and 4B is able to be substantially similar to the pitchpropelled vehicle 100 described in FIGS. 1A-E except for the differencesdescribed herein. In particular, detailed description and/orillustration of the shared features of the vehicles 100 and 400 has beenomitted for the sake of brevity. As shown in FIGS. 4A and 4B, the board102 of the vehicle 400 is separated into two sections 402 a, 402 b thatare pivotably coupled by one or more folding hinges 404 such that thetwo boards are able to pivot with respect to each other about the axisformed by a pin (or pins) 406 of the hinges 404. In some embodiments, asshown in FIG. 4A-4D, the pin (or pins) 406 is/are able to be the axle ofthe wheel 104 (around which the wheel 104 rotates) such that the hinges404 are coupled to and pivot around the axle when folding and unfolding.Alternatively, one or more of the pins 406 are able to be separate fromthe axle of the vehicle 400. In such embodiments, the pins 406 (and thusthe axis formed by the pins about which the sections rotate) are able toaligned or unaligned with the axle of the vehicle 400. In someembodiments, the hinges 404 are embedded within a cavity of the board102 (e.g. between the faces of the two sections 402 a, 402 b that toucheach other when the board 102 is in the unfolded position).

As shown in FIGS. 4C and 4D, the board 102 is able to comprise one ormore handles 408 a, 408 b for making the board 102 easier to hold whenfolded or unfolded. In some embodiments, one or more of the handles 408a, 408 b comprise an aperture or hole that extend all the way throughthe board 102 such that a user is able to put their hand through theaperture in order to grip the handle 408 a, 408 b. Alternatively, one ormore of the handles 408 a, 408 b are able to comprise channels orcavities within the board 102 that dig into but do not extend all theway through the board 102. For example, the cavities of the handle orhandles 408 a, 408 b are able to project into the bottom of the board102 but not extend through to the top of the board 102. In someembodiments, the handles 408 a, 408 b are positioned on the ends of theboard 102 such that when the board 102 is fully folded and the two endsare adjacent, touching and/or abut each other (as shown in FIGS. 4B and4D), apertures of the handles 408 a, 408 b are aligned or overlap suchthat a user is able to put a hand through both of the apertures at thesame time. Although as shown in FIGS. 4C and 4D, the board 102 comprisestwo handles 408 a, 408 b at the two ends of the board 102, more or lesshandles 408 a, 408 b are contemplated positioned in the same ordifferent positions on the board 102.

In some embodiments, the faces or surfaces of the two sections 402 a,402 b of the board 102 that touch or abut each other when the board 102is in the unfolded position (as shown in FIG. 4A) are able to compriseone or more detachably coupling electrical interfaces (not shown) thatfacilitate operative/electrical coupling of elements of the driveassembly 106 that are located on different sections 402 a, 402 b. Forexample, the interfaces are able to electrically, communicatively and/oroperatively couple together one or more first elements of the driveassembly 106 on the section 402 a to one or more second elements of thedrive assembly 106 on the section 402 b when the board 102 is in theunfolded position, wherein the first and second elements are uncoupledwhen the board 102 is in the folded position. In some embodiments, thefaces or surfaces of the two sections 402 a, 402 b of the board 102 thattouch or abut each other when the board 102 is in the unfolded position(as shown in FIG. 4A) are able to comprise one or more fasteners 410that detachably couple the two faces together in the unfolded position.In such embodiments, the fasteners 410 are able to include a lockingmechanism that prevents the fasteners from detaching the two facesunless the locking mechanism is unlocked. Similarly, in someembodiments, the ends of the two sections 402 a, 402 b of the board 100that touch or abut each other when the board 100 is in the foldedposition (as shown in FIG. 4B) are able to comprise one or morefasteners 412 that detachably couple the two ends together in the foldedposition. In such embodiments, the fasteners 412 are able to include alocking mechanism that prevents the fasteners 412 from detaching the twoends unless the locking mechanism is unlocked. Alternatively, one ormore of the fasteners 410, one or more of the fasteners 412 and/or oneor more of the electrical interfaces are able to be omitted.

In some embodiments, if the vehicle 100 comprises a hollow axle aroundwhich the wheel 104 rotates (e.g. the hollow axle within the wheel 104as shown in FIGS. 1A-1E), the pins 406 are able to be coupled to ahollow axle such that the sections 402 a, 402 b pivot about the pins 406as coupled to the hollow axle. Alternatively, the hinges 404 are able tobe omitted and instead the two sections 402 a, 402 b are able to slidealong the guard 103 (e.g. via a rail or track that slidably couples thesections 402 and the guard 103). In some embodiments, the grips 108 areable to be omitted or are also able to slide along with the sections 402a, 402 b such that they do not block the sliding of the sections 402 a,402 b. Although, as shown in FIGS. 4A-D, the board 102 comprises oneaxis (created by two hinges 404) about which two sections 402 a, 402 bare able to fold/pivot any number of hinges 404 enabling any number ofsections 402 to fold/pivot about any number of axis is contemplated. Forexample, as shown in FIGS. 4E and 4F, in some embodiments the vehicle400 is able to comprise two sets of hinges 404 are able to enable twoaxis upon which three sections 402 a, 402 b, 402 c of the board 102 areable to pivot. Additionally, although as shown in FIGS. 4A-D the hinges404 are positioned such that the pivot axis are perpendicular to thewheel 104 (and the elongated dimension of the board 102), othernon-perpendicular angles of the pivot axis are contemplated. Thus, thevehicle 400 provides the benefit of enabling the folding and unfoldingof the board 102 in order to save space during storage of the vehicle400.

FIG. 5 illustrates a flow chart of a method of using a pitch propelledvehicle with a folding feature according to some embodiments. As shownin FIG. 5, a vehicle 100, 400 having a folding feature is provided atthe step 502. One or more sections 402 of the board 102 arepivoted/rotated about one or more axis via one or more hinges 404 suchthat the board 102 is in a folded position at the step 504. In someembodiments, the method comprises two or more ends of the board 102 fromdifferent sections 402 of the board 102 being coupled together in thefolded position with one or more fasteners 412. In some embodiments, thefasteners 412 are locked together in the folding position with a lockingmechanism. One or more sections 402 of the board 102 are pivoted/rotatedabout one or more axis via one or more hinges 404 such that the board102 is in an unfolded position at the step 506. In some embodiments, themethod comprises two or more faces of the board 102 from differentsections 402 of the board 102 being coupled together in the foldedposition with one or more fasteners 410. In some embodiments, thefasteners 410 are locked together in the folding position with a lockingmechanism. In some embodiments, one or more steps of the methoddescribed in FIG. 5 is able to be combined with the method described inFIG. 3 in order to describe a method of operating and/or folding thevehicle. As a result, the method provides the advantage of enabling theboard 102 to be folded such that it occupies a smaller area when storedor not in use.

The present invention has been described in terms of specificembodiments incorporating details to facilitate the understanding ofprinciples of construction and operation of the invention. Suchreference herein to specific embodiments and details thereof is notintended to limit the scope of the claims appended hereto. It will bereadily apparent to one skilled in the art that other variousmodifications may be made in the embodiment chosen for illustrationwithout departing from the spirit and scope of the invention as definedby the claims. For example, in some embodiments the drive assembly 106is able to comprise a locking module or mechanism that enables a user tolock the vehicle in order to prevent theft. In particular, thecontroller 106 c is able to be configured to prevent the vehicle 100from operating unless a password is received via a user input, a RFsignal is received that matches a predetermined signal, bluetoothconnection is made to a mobile computing device having an identifierthat is recognized, and/or other appropriate locking/unlocking methods.

1. A vehicle for carrying a user comprising: a board having a pluralityof detached sections coupled together by one or more hinges wherein thesections are able to pivot about the hinges; a ground-contacting membercoupled with the board; and a motorized drive assembly coupled with theground-contacting member, wherein the ground-contacting member rotatesabout an axle and the axle acts as a pin of the hinges, wherein thesections pivot about the axle.
 2. The vehicle of claim 1, wherein theground-contacting member rotates about a hollow axle having an exposedchannel that extends though the hollow axle.
 3. (canceled)
 4. Thevehicle of claim 1, wherein the board has one or more additional hingesthat with the one or more hinges rotatably couple together three of thesections of the board.
 5. The vehicle of claim 1, wherein the boardcomprises one or more handles that are each defined by one of the groupconsisting of a hole that extends through the board or a channel thatextends only partially into the bottom of the board.
 6. The vehicle ofclaim 1, wherein two or more of the sections of the board house at leastone electronic component of the drive assembly and the board furthercomprises one or more interfaces that electrically couple together twoor more of the electronic components from different ones of the two ormore of the sections when the board is in an unfolded position.
 7. Thevehicle of claim 1, further comprising one or more sensors coupled withthe drive assembly, wherein the drive assembly adjusts the velocity ofthe ground-contacting member based on one or more distances of the boardfrom a surface below the board as detected by the sensors.
 8. Thevehicle of claim 7, wherein the board is elongated along a dimension ina fore-aft plane that aligns with the forward and reverse directions oftravel of the vehicle.
 9. The vehicle of claim 8, wherein one or morefore sensors of the sensors are positioned at the fore end of theelongated dimension of the board and one or more aft sensors of thesensors are positioned at the aft end of the elongated dimension of theboard.
 10. The vehicle of claim 7, wherein the drive assembly adjuststhe velocity of the ground-contacting member based on the one or moredistances by using the distances to calculate a pitch of the board withrespect to the surface and applying a force to the ground-contactingmember in order to achieve a predefined velocity of theground-contacting member that corresponds to the pitch.
 11. The vehicleof claim 10, wherein the pitch is calculated by determining a differencebetween the one or more distances and an average of two or more of thedistances such that the drive assembly adjusts for unevenness in thesurface.
 12. The vehicle of claim 8, wherein the board as balanced bythe ground-contacting member is unstable with respect to tipping alongthe fore-aft plane when the motorized drive assembly is not inoperation, and the motorized drive assembly is configured toautomatically balance the board with respect to tipping along thefore-aft plane when the motorized drive assembly is in operation.
 13. Amethod of operating a vehicle having an elongated board, the methodcomprising: providing a vehicle comprising: a board having a pluralityof detached sections coupled together by one or more hinges wherein thesections are able to pivot about the hinges; a ground-contacting membercoupled with the board; and a motorized drive assembly coupled with theground-contacting member; moving the board between an unfolded positioninto a folded position by pivoting the sections about the hinges,wherein ends of two of the sections that are on opposite sides of theboard in the unfolded position are closer together in the foldedposition, wherein the ground-contacting member rotates about an axle andthe axle acts as a pin of the hinges, wherein the sections pivot aboutthe axle.
 14. The method of claim 13, wherein the ground-contactingmember rotates about a hollow axle having an exposed channel thatextends though the hollow axle.
 15. (canceled)
 16. The method of claim13, wherein the board has one or more additional hinges that with theone or more hinges rotatably couple together three of the sections ofthe board.
 17. The method of claim 13, wherein the board comprises oneor more handles that are each defined by one of the group consisting ofa hole that extends through the board or a channel that extends onlypartially into the bottom of the board.
 18. The method of claim 13,wherein two or more of the sections of the board house at least oneelectronic component of the drive assembly and the board furthercomprises one or more interfaces that electrically couple together twoor more of the electronic components from different ones of the two ormore of the sections when the board is in an unfolded position.
 19. Themethod of claim 13, wherein the vehicle further comprises one or moresensors coupled with the drive assembly, wherein the drive assemblyadjusts the velocity of the ground-contacting member based on one ormore distances of the board from a surface below the board as detectedby the sensors.
 20. The method of claim 19, wherein the board iselongated along a dimension in a fore-aft plane that aligns with theforward and reverse directions of travel of the vehicle.
 21. The methodof claim 20, wherein one or more fore sensors of the sensors arepositioned at the fore end of the elongated dimension of the board andone or more aft sensors of the sensors are positioned at the aft end ofthe elongated dimension of the board.
 22. The method of claim 19,wherein the drive assembly adjusts the velocity of the ground-contactingmember based on the one or more distances by using the distances tocalculate a pitch of the board with respect to the surface and applyinga force to the ground-contacting member in order to achieve a predefinedvelocity of the ground-contacting member that corresponds to the pitch.23. The method of claim 22, wherein the pitch is calculated bydetermining a difference between the one or more distances and anaverage of two or more of the distances such that the drive assemblyadjusts for unevenness in the surface.
 24. The method of claim 20,wherein the board as balanced by the ground-contacting member isunstable with respect to tipping along the fore-aft plane when themotorized drive assembly is not in operation, and the motorized driveassembly is configured to automatically balance the board with respectto tipping along the fore-aft plane when the motorized drive assembly isin operation.
 25. (canceled)
 26. A vehicle for carrying a usercomprising: a board having a plurality of detached sections coupledtogether by one or more hinges wherein the sections are able to pivotabout the hinges; an axle acting as a pin of the hinges, wherein thesections pivot about the axle; a ground-contacting member coupled withthe board and rotating about the axle; and a motorized drive assemblycoupled with the ground-contacting member.
 27. The vehicle of claim 26,wherein the ground-contacting member rotates about a hollow axle havingan exposed channel that extends though the hollow axle and furtherwherein the axle fits through the hollow axle.
 28. The vehicle of claim26, wherein the board has one or more additional hinges that with theone or more hinges rotatably couple together three of the sections ofthe board.
 29. The vehicle of claim 26, wherein the board comprises oneor more handles that are each defined by one of the group consisting ofa hole that extends through the board or a channel that extends onlypartially into the bottom of the board.
 30. The vehicle of claim 26,wherein two or more of the sections of the board house at least oneelectronic component of the drive assembly and the board furthercomprises one or more interfaces that electrically couple together twoor more of the electronic components from different ones of the two ormore of the sections when the board is in an unfolded position.
 31. Thevehicle of claim 26, further comprising one or more sensors coupled withthe drive assembly, wherein the drive assembly adjusts the velocity ofthe ground-contacting member based on one or more distances of the boardfrom a surface below the board as detected by the sensors.
 32. Thevehicle of claim 31, wherein the board is elongated along a dimension ina fore-aft plane that aligns with the forward and reverse directions oftravel of the vehicle.
 33. The vehicle of claim 32, wherein one or morefore sensors of the sensors are positioned at the fore end of theelongated dimension of the board and one or more aft sensors of thesensors are positioned at the aft end of the elongated dimension of theboard.
 34. The vehicle of claim 31, wherein the drive assembly adjuststhe velocity of the ground-contacting member based on the one or moredistances by using the distances to calculate a pitch of the board withrespect to the surface and applying a force to the ground-contactingmember in order to achieve a predefined velocity of theground-contacting member that corresponds to the pitch.
 35. The vehicleof claim 34, wherein the pitch is calculated by determining a differencebetween the one or more distances and an average of two or more of thedistances such that the drive assembly adjusts for unevenness in thesurface.
 36. The vehicle of claim 32, wherein the board as balanced bythe ground-contacting member is unstable with respect to tipping alongthe fore-aft plane when the motorized drive assembly is not inoperation, and the motorized drive assembly is configured toautomatically balance the board with respect to tipping along thefore-aft plane when the motorized drive assembly is in operation.